Cryptosporidium is a genus of apicomplexan parasites that inhabit the respiratory and gastrointestinal tracts of vertebrates. Research of these parasites is limited by a lack of model hosts. This study aimed to determine the extent to which infection at the embryo stage can enhance the propagation of Cryptosporidium oocysts in chickens. Nine-day-old chicken embryos and one-day-old chickens were experimentally infected with different doses of Cryptosporidium baileyi and Cryptosporidium parvum oocysts. Post hatching, all chickens had demonstrable infections, and the infection dose had no effect on the course of infection. Chickens infected as embryos shed oocysts immediately after hatching and shed significantly more oocysts over the course of the infection than chickens infected as one-day-olds. In chickens infected as embryos, C. baileyi was found in all organs except the brain whereas, C. parvum was only found in the gastrointestinal tract and trachea. In chickens infected as one-day-olds, C. baileyi was only found in the gastrointestinal tract and trachea. Chickens infected as embryos with C. baileyi died within 16 days of hatching. All other chickens cleared the infection. Infection of chickens as embryos could be used as an effective and simple model for the propagation of C. baileyi and C. parvum.

隐孢子虫是居住在脊椎动物的呼吸道和胃肠道中的apicomplexan寄生虫的属。这些寄生虫的研究受到缺乏模型宿主的限制。这项研究旨在确定在胚胎阶段感染可以在多大程度上增强隐孢子虫卵囊在鸡体内的繁殖。用不同剂量的百日隐孢子虫和小隐孢子虫感染了9天大的鸡胚和1天大的鸡卵囊。孵化后，所有鸡均具有明显的感染，并且感染剂量对感染过程没有影响。孵化后被胚胎感染的鸡会立即脱落卵囊，并且在感染过程中会比一天大的鸡流掉更多的卵囊。在以胚胎感染的鸡中，除大脑外，所有器官都发现了百日咳杆菌，而小肠念珠菌仅在胃肠道和气管中被发现。在感染了一天大的鸡中，百日咳衣原体仅在胃肠道和气管中发现。感染与胚胎鸡C.鼢鼠孵化后16天内死亡。其他所有鸡都清除了感染。鸡作为胚胎的感染可以作为一种有效和简单的传播鲍氏梭菌和小杯梭菌的模型。